1. Field of the Invention
The present invention relates to an ink cartridge which is to be used with an ink-jet recording apparatus and is constructed so as to feed ink to a recording head. The present invention also relates to an ink-jet recording apparatus using the ink cartridge.
2. Description of the Related Art
An ink-jet recording apparatus produces comparatively low noise during printing operation and can form small dots at high density. Hence, the ink-jet recording apparatus has recently been used in a number of printing applications, including color printing.
Such an ink-jet recording apparatus is usually equipped with an ink-jet recording head which is mounted on a carriage and moved in the widthwise direction of recording paper, and paper feed means for moving the recording paper in the direction orthogonal to the traveling direction of the recording head. On the basis of print data, ink droplets are ejected from the recording head, thus recording the data on the recording paper.
The recording head is mounted on the carriage, and is capable of ejecting ink droplets of, for example, black, yellow, cyan, and magenta. Accordingly, the ink-jet recording apparatus enables full-color printing by changing the proportions of ink types, as well as effecting text printing with black ink.
Incidentally, in order to effect a comparatively-high volume of printing, a recording apparatus of this type supplied for, for example, an office or business purpose, requires use of high-volume ink cartridges. To this end, there has been provided a recording apparatus, in which ink cartridges are fitted to a cartridge holder provided, for example, to an apparatus main body.
In the recording apparatus, sub-tanks are disposed on the carriage having the recording head, and the respective sub-tanks are replenished with ink from corresponding ink cartridges by way of ink supply tubes. The sub-tanks, in turn, supply ink to the recording head.
Recently, growing demand exists for a large-size recording apparatus capable of effecting printing on larger-size paper, in which a carriage travels a longer scan distance. In order to improve throughput of such a recording apparatus, a larger number of nozzles are provided in a recording head.
Further, demand exists for a recording apparatus which sequentially supplies ink to the respective sub-tanks mounted on the carriage from corresponding ink cartridges while performing printing operation, in order to improve throughput, and which stably supplies ink from the respective sub-tanks to the recording head.
In such a recording apparatus, since the carriage travels over a longer scan distance, the lengths of respective ink supply tubes inevitably increase. Further, as mentioned above, a larger number of nozzles are provided in the recording head. Hence, such a recording apparatus encounters a technical problem of deficient ink supply to the sub-tanks because the recording head consumes a large quantity of ink, and an increase in the dynamic pressure (i.e., pressure loss) of ink is likely to occur within each of the ink supply tubes interconnecting the ink cartridges and the sub-tanks.
As one measure to prevent this technical problem, there may be employed, for example, a construction in which air pressure is applied to the ink cartridges to forcibly inducing ink flows from the ink cartridges to the sub-tanks under air pressure. This construction makes it possible to supply a sufficient amount of ink to the sub-tanks.
FIG. 36 is a cross-sectional view showing an example construction of a related-art ink cartridge utilized for such an ink-jet recording apparatus. In FIG. 36, reference numeral 81 designates a case defining the outer shell of an ink cartridge. The case 81 is integrally formed, into a shape of a bottle having a relatively large opening, from synthetic resin material by means of blow molding (hollow molding).
A columnar cap member 84 is fitted into an opening section 82 by way of an O-ring 83. By means of the cap member 84 and the O-ring 83, the inside of the case 81 is sealed, thus constituting a pressure chamber 85 within the case 81.
An ink outlet section 86 employing a ball valve is formed in the center of the columnar cap member 84. Ink can be led out from an ink pack 87xe2x80x94which is housed in the case 81 and formed from ink-filled flexible materialxe2x80x94to the outside via the ink outlet section 86.
An air inlet port 89 is formed in a portion of the cap member 84. A rubber plug 88 is fitted on the air inlet port 89. A through hole 88a is formed in the center of the rubber plug 88. When the ink cartridge is not attached to an ink-jet recording apparatus, the through hole 88a is closed.
When the ink cartridge is attached to the recording apparatus, an unillustrated hollow needle provided on the recording apparatus penetrates through the through hole 88a of the rubber plug 88, and pressurized air can enter the pressure chamber 85 by way of the hollow needle.
Consequently, the pressurized air is introduced into the pressure chamber 85 by way of the hollow needle. Upon receipt of pressure, the ink contained in the ink pack 87 is led to the outside by way of the ink outlet section 86.
The above ink cartridge of related-art construction involves several problems to be solved, as described below.
A first problem is as follows: In the ink cartridge of the related-art construction mentioned above, the case forming the outer shell is integrally formed by blow molding, and consequently, as can be seen from the exemplified construction shown in FIG. 36, the ink pack 87 is integrally attached to the columnar cap member 84 formed with the ink replenishing valve 86 and the air introducing valve 88.
The cap member 84 is pressure-fitted to the opening section 82 using the O-ring 83 so that the ink pack 87, which has not been filled with ink, is inserted into the case 81. Subsequently, ink is injected into the ink pack 87 from the exterior via the ink replenishing valve 86 to thereby complete a product, i.e. the ink cartridge.
Since the case defining the outer shell of the ink cartridge of related-art construction is integrally formed by blow molding, difficulty is often encountered in assembling an ink pack, which has already filled with ink, into the case. That is, the ink pack must be filled with ink in a subsequent process.
Further, predetermined pressure is imposed on the inside of the case during the recording operation of the recording apparatus. There must be employed a countermeasure for preventing deformation of the case, which would otherwise be caused when the case receives the pressure. For this reason, in order to ensure the strength of the case, adoption of a simple construction, such as a cylindrical shape like a bottle having a relatively large opening section as shown in FIG. 36, is preferable.
However, such an outer shell yields a problem of an increase in the occupation volume of the case, resulting in difficulty in designing the layout of a recording apparatus of this type, which requires parallel arrangement of color ink cartridges.
Another conceivable measure for ensuring the strength of the case is to increase the thickness of the case. However, a large quantity of synthetic resin material is consumed for forming a case, thus posing difficulty in contributing to conservation of resources.
In contrast, another conceivable measure for reducing the quantity of synthetic resin material consumed is to integrally form reinforcement ribs on a part of the case. However, as mentioned above, when blow molding is employed for forming a case, forming reinforcement ribs in the interior of the case is usually difficult.
A second problem is that, in a case where ink cartridges of related-art construction attached to a recording apparatus are removed from the recording apparatus after having performed ink supply operation, the through hole 88a formed in the rubber plug 88 is closed immediately due to elasticity of rubber, thereby leaving pressurized air within the pressure chamber 85.
The pressurized air remaining in the pressure chamber 85 continues pressurizing the ink pack 87.
If the ball constituting the ink outlet section 86 is pushed unintentionally or intentionally through use of, for example, a pen tip or similar implement, the ink contained in the ink pack 87 gushes forth, thereby soiling the surrounding areas.
Another problem is that ink may leak out from the ink outlet section 86 even when the pushing action is not performed.
In order to prevent occurrence of such problems, there must be taken measures for actively letting the air pressure escape from the inside of the pressure chamber 85, by inserting a hollow needle, such as an injection needle, into the through hole 88a of the rubber plug 88 when the ink cartridge is removed from the recording apparatus.
However, such an operation for releasing pressure is cumbersome for the user, and this is not the reliable countermeasure in practice.
Even when the ink cartridge of related-art construction is stored without being attached to the recording apparatus, the ambient temperature change of the location where the ink cartridge is stored, particularly, the ambient temperature increase causes the internal atmospheric pressure of the pressure chamber 85 to increase. Accordingly, ink leaks out from the ink outlet section 86.
A natural approach is to construct an ink cartridge which supplies ink by introducing pressurized air into a case, such that the inside of the case is held hermetic over a long period of time during actual use of the ink cartridge. In addition, consideration of ease of assembly and ease of disassembly and recycling is particularly important. Fulfillment of these requirements is sought strongly.
When primarily text data are to be printed, the ink-jet recording apparatus utilizing the ink cartridge of such construction employs black ink, as is well known. When color printing is to be effected, color inks, such as yellow ink, magenta ink, and cyan ink, are used.
As set forth, the ink is available while an ink pack formed from flexible material in the form of a bag is filled with ink and the ink pack is housed in a cartridge case defining the outer shell of the ink cartridge. The ink cartridges are formed so as to assume substantially identical outer shapes. Further, the ink cartridges are filled with substantially-identical amounts of ink.
In a case where the majority of printed matter to be produced by a recording apparatus is, for example, text data, the amount of color ink used and the frequency of use of color ink are low. Hence, the color ink cartridges will become empty considerably later than will a black ink cartridge.
For this reason, expiration dates of color ink arrive before the color ink cartridges become empty, thus involving replacement of the ink cartridges with new ink cartridges.
Conversely, when the recording apparatus is used for printing a large number of color images, the amount of black ink used and the frequency of use of black ink are low. The black ink cartridge will become empty much later than will the color ink cartridges. Hence, the expiration date of black ink arrives while black ink still remains in the cartridge.
Thus, in addition to a problem of imposing running costs on the user, there arises another problem of a load of disposing of a considerable amount of ink remaining in an ink cartridge which itself is to be disposed of.
A conceivable measure for diminishing running costs and the load of disposing of ink is to provide an ink cartridge filled with a smaller amount of ink. In this case, there may be adopted regulation means for diminishing the amount of ink contained in an ink pack.
For convenience of attaching a cartridge into a holder of a recording apparatus, the outer shell of an ink cartridge case for housing an ink pack must be of a certain size and shape, regardless of the volume of ink. In an ink cartridge filled with a smaller amount of ink, a large gap arises between the cartridge case and the ink pack.
For example, in the event that an ink pack is freely moved within the cartridge case because of vibration stemming from transport of an ink cartridge; particularly, in the event that the ink pack has experienced excessive physical shock, the ink pack will be broken.
Another conceivable measure to prevent breakage of an ink pack is to make the outer dimensions of cartridge cases identical and to change the internal size and shape of the case in accordance with the amount of ink to be contained. In a case where an attempt is made to adopt such a measure, metal molds to be used for molding ink cartridge cases must be prepared separately for a high-volume ink cartridge and for a low-volume ink cartridge, and costs of the metal molds are reflected in manufacturing costs.
In connection with a recording apparatus which is constructed so as to push ink from an ink cartridge by means of pressurized air and which enables selective use of high-volume ink packs and low-volume ink packs, when low-volume ink cartridges are used, a large amount of pressurized air must be introduced into the cartridge cases.
Consequently, for example, when an attempt is made to activate the recording apparatus by turning on the operating power of the recording apparatus, consumption of a considerable amount of time is required before the recording apparatus becomes able to print, thereby deteriorating the throughput of the recording apparatus.
The present invention has been conceived in light of the foregoing technical drawbacks and is aimed at providing an ink cartridge which facilitates a process for assembling the outer shell of an ink cartridge including an ink pack, facilitates disassembly and recycling of a waste cartridge case, and can contribute to conservation of resources.
The present invention is also aimed at providing an ink cartridge which supplies ink using air pressure and can prevent gushing or leaking of ink, which would otherwise be caused by residual air pressure or variations in ambient temperature.
The present invention is also aimed at providing an ink cartridge which ensures a stable hermetic state within a case and facilitates assembly and disassembly operations.
The present invention is also aimed at providing an ink cartridge capable of effectively preventing fracture of an ink pack, which would otherwise be caused when an ink cartridge filled with a small volume of ink is subjected to physical shock.
The present invention is also aimed at providing an ink cartridge for use with a recording apparatus which pushes ink from an ink cartridge by utilization of pressurized air, wherein, when a low-volume ink cartridge is used, the ink cartridge can prevent deterioration of throughput of the recording apparatus.
The present invention is also aimed at providing an inkjet recording apparatus suitable for use with the ink cartridge.
To achieve the objects, the present invention provides an ink cartridge for use with a recording apparatus which supplies ink to a recording head by application of pressurized air produced by an air pressurization pump, comprising:
an ink pack which is formed from ink-filled flexible material and housed in the ink cartridge;
an outer shell member which is formed by coupling together at least a first outer shell constituent member and a second outer shell constituent member such that the outer shell member is hermetically sealed; and
a pressure chamber which is formed by the outer shell member and the ink pack and to which the pressurized air produced by the air pressurization pump is to be applied.
Preferably, the first outer shell constituent member and the second outer shell constituent member are hermetically coupled together by vibratory welding.
Preferably, a weld surface is formed over the entirety of a peripheral edge of a lower case acting as the first outer shell constituent member so as to constitute a substantially-flat single plane, and a director which is to be frictionally welded upon contact with the weld surface formed on the peripheral edge of the lower case is formed on a peripheral edge of an upper case acting as the second outer shell constituent member.
Preferably, an upright flange section is integrally formed on the peripheral edge of the lower case serving as the first outer shell constituent member, along the outer periphery of the weld plane.
Moreover, a reinforcement rib is preferably formed preliminarily on a surface of the first outer shell constituent member defining the pressure chamber, as well as on a surface of the second outer shell constituent member defining the pressure chamber.
Preferably, the first outer shell constituent member and the second outer shell constituent member are hermetically coupled together by heat-welding.
Preferably, a weld surface is formed over the entirety of a peripheral edge of a lower case acting as the first outer shell constituent member so as to constitute a substantially-flat single plane, and a heat-welding film acting as the second outer shell constituent member is formed on the weld surface formed on the peripheral edge of the lower case.
Preferably, the ink cartridge further comprises a reinforcement member for covering the outside of the heat-welding film acting as the second outer shell constituent member.
Preferably, an engagement section removably engaging the peripheral edge of the lower case acting as the first outer shell constituent member is formed integrally along the peripheral edge of the reinforcement member.
In this case, a reinforcement rib for preventing deformation caused by air pressure is preferably formed preliminarily on the surface of the first outer shell constituent member defining the pressure chamber.
Preferably, a contact surface is formed over the entirety of a peripheral edge of a lower case acting as the first outer shell constituent member; a contact surface to be brought into close contact with the contact surface formed on the peripheral edge of the lower case is formed on a peripheral edge of a cover acting as the second outer shell constituent member; and an engagement section removably engaging the peripheral edge of the lower case is formed integrally on the cover, thereby maintaining the case and the cover in a sealed state by the action of the engagement section.
In the ink cartridge according to the present invention which has been embodied in the manner as mentioned above, an outer shell member is formed by coupling together at least a first outer shell constituent member and a second outer shell constituent member such that the outer shell member is hermetically sealed. Further, the pressurized air produced by the air pressurization pump is to be applied to a pressure chamber which is formed by the outer shell member and the ink pack.
As a method of hermetically coupling together the first outer shell constituent member and the second outer shell constituent member, vibratory welding can be used.
The first outer shell constituent member and the second outer shell constituent member may be hermetically coupled together by heat welding.
It is also possible to adopt a method of sustaining the first and second outer shell constituent members in a hermetic state such that a contact surface formed on the second outer shell constituent member is arranged so as to come into close contact with a contact surface formed on the first outer shell constituent member.
In a case where the first outer shell constituent member is taken as a lower case and where the second outer shell constituent member is taken as an upper case, an ink-filled ink pack is housed in the lower case preliminarily. In this state, the coverserving as an upper case is hermetically connected to the lower case through use of any one of the above-mentioned methods, thus providing an ink cartridge product.
Consequently, the process of assembling the outer shell of an ink cartridge including an ink pack can be simplified, thus contributing to productivity of a product of this type.
Since the outer shell of the ink cartridge is formed by hermetically coupling or joining together the first and second outer shell constituent members, disassembly and recycling of a waste cartridge are facilitated, thereby contributing to conservation of resources.
The present invention also provides an ink cartridge constructed so as to supply ink to a recording head by application of pressurized air produced by an air pressurization pump, comprising:
an ink pack which is formed from ink-filled flexible material and housed in the ink cartridge;
a pressure chamber which is formed between an outer shell member of the ink cartridge and the ink pack and to which the pressurized air produced by the air pressurization pump is to be applied;
a pressurized air inlet port which is formed in the outer shell member of the ink cartridge for enabling introduction of the pressurized air supplied from the air pressurization pump; and
an ink outlet section which is formed in the ink pack and enables outflow of ink from the ink pack, wherein, when the ink cartridge is removed from the recording apparatus, the pressurized air inlet port is released, to thereby bring the pressure chamber in communication with the atmosphere, and the ink outlet section is brought into a closed state.
In this case, the pressurized air inlet port is preferably formed integrally with the outer shell member of the cartridge and from a cylindrical member which defines an air channel communicating with the pressure chamber.
Preferably, the ink outlet section provided in the ink pack is equipped with a valve member, wherein, when the ink cartridge is mounted to a recording apparatus, the valve member comes into contact with a connection section of the recording apparatus and recedes in an axial direction, thus becoming open. Further, when the ink cartridge is removed from the recording apparatus, the valve member advances in the axial direction, thus sustaining a closed state.
In this case, in the preferred embodiment, the ink outlet section is equipped with a spring member for urging the valve member so as to advance in the axial direction.
In addition, the ink outlet section is exposed to the outside of the outer shell member through an opening section formed in the outer shell member of the ink cartridge, and an O-ring is interposed between the opening section and the ink outlet section. Further, an engagement member is preferably provided for establishing a sealed state between the opening section and the ink outlet section by pressing the O-ring.
In the ink cartridge according to the present invention, when the ink cartridge is mounted to a recording apparatus, pressurized air produced by the air pressurization pump is introduced into the pressure chamber from the pressurized-air inlet port. The ink filled in the ink pack is supplied to the recording apparatus through the ink outlet section upon receipt of pressurized air.
When the ink cartridge is removed from the recording apparatus, the pressurized-air inlet portxe2x80x94which is formed in the outer shell member of the ink cartridge and is formed cylindricallyxe2x80x94is released, whereby the pressure chamber is immediately brought into communication with the atmosphere. Consequently, the ink pack stored in the ink cartridge is also immediately released from a pressurized state.
Therefore, a problem of gushing or leakage of ink from the ink outlet section provided in the ink pack can be eliminated.
Even in a state in which an ink cartridge is not mounted to the recording apparatus and is stored, the pressure chamber is in communication with the atmosphere at all times, thus eliminating an influence of ambient temperature.
The present invention also provides an ink cartridge for use with a recording apparatus including: an ink pack formed from ink-filled flexible material and filled with ink, and a cartridge case hermetically formed for housing the ink pack, wherein, when the ink cartridge is mounted to a recording apparatus, pressurized air is introduced into the cartridge case, comprising:
first and second cases which constitute the cartridge case;
a flange section formed along an edge of an opening of the first case; and
a lug-shaped member which is formed on the second case and engages with the flange section, thereby coupling the first and second cases together.
Preferably, as an ink pack is housed in the first case, the edge of the opening of the case is sealed by a film member, thus realizing a sealed state, and the second case serves as a cover for preventing expansion of the film member when the film member receives pressurized air.
In this case, a tapered surface and an engagement step section are preferably formed on each lug-shaped member such that, when the second case is attached to the first case, the tapered surface goes beyond the flange section formed on the first case and such that the engagement step section engages the flange section.
Preferably, the second case has a planar section acting as a cover and a fold section formed integral with and perpendicular to the planar section, and the lug-shaped member is formed on an interior surface of the fold section.
In this case, a plurality of independent lug-shaped members are preferably formed intermittently on an interior surface of the fold section. Preferably, slit holes are formed through a planar section of the second case to correspond in location to the plurality of independent lug-shaped members, along the fold section.
In a preferred embodiment, a film member is sealed to the edge of the opening of the first case by heat welding.
In the ink cartridge according to the present invention, the ink pack which is formed from flexible material and is filled with ink is sealed with a film member while housed in the first case.
The second case is joined to the first case housing the ink pack, whereby the second case acts as a cover for preventing expansion of the film member when the film member is subjected to pressurized air.
Consequently, the hermetic state of the ink cartridge is ensured by the film member. Deformation of the film member, which would otherwise be caused when the film member is subjected to pressurized air, is effectively prevented by the second case acting as a cover.
In a case where the second case is coupled or joined to the first case, the lug-shaped member formed on the second case is engaged with the flange section formed along the edge of the opening of the first case. The first and second cases are joined together, thus constituting the outer shell of the ink cartridge.
Consequently, assembly and disassembly of an ink cartridge are readily achieved, thereby contributing to improving the ease of recycling of the constituent members of the ink cartridge.
The lug-shaped member formed on the second case is formed on the interior surface of the fold section perpendicular to the plane section acting as a cover. The provision of a tapered surface and an engagement section which go beyond the flange section formed on the first case, makes it easy to join the first case and the second case together. That is, a simple operation of stacking the first and second cases, and pushing one to the other can join the first and second cases. Accordingly, this arrangement contributes to ease of assembly of an ink cartridge.
Since the slit holes are formed through the planar section of the upper case to correspond in location to the lug members along the fold section, the fold section having the lug members formed thereon can be improved in terms of ease of flexure. The ease of flexure of the fold section effectively acts to provide relief when the tapered surface of each of the lug members goes beyond the flange section of the first case.
With such relief, it is possible to effectively avoid, for example, a problem of whitening of the area in which the lug members are formed or a problem of cracks, which would otherwise be caused when undue stress acts on the lug members when the upper and lower cases, both being made of synthetic resin, are attached together.
In the ink cartridge having the foregoing construction, when the ink cartridge is mounted to a recording apparatus and pressurized air is introduced into a case, the planar section of the second case undergo slight outward deformation by way of the film member, and consequently the lug-shaped member formed on the interior surface of the fold section orthogonal to the planar section is inwardly inclined due to the deformation of the planar section.
Therefore, the lug-shaped member positively engages the flange section of the second case, thereby sustaining the first and second cases in a strongly coupled state.
The present invention also provides an ink cartridge for use with a recording apparatus including an ink pack formed from flexible material and filled with ink and a cartridge case which houses the ink pack and constitutes an outer shell, comprising:
an ink pack press member which is housed in the cartridge case along with the ink pack and which adjusts the volume of ink to be poured into the ink pack in accordance with the volume of the press member.
Preferably, the ink pack is formed into a substantially rectangular shape and into a bag by sealing four sides of the ink pack, and the press member housed in the cartridge along with the ink pack is formed into a frame shape having a window-shaped opening in the central portion thereof. Further, four sides of the ink pack are pressed by the frame-shaped press member.
In this case, the portions of the press member opposing the four sides of the ink pack are formed into tapered shapes such that the portions become gradually thinner toward the window-shaped opening formed in the center of the press member to define slope surfaces.
Preferably, the slope surfaces are formed into curved surfaces, and the press member is formed from resilient material.
Preferably, the cartridge case is hermetically formed, and, as pressurized air is introduced into the case while the ink cartridge is mounted to a recording apparatus, the ink pack is pressurized by air pressure.
Preferably, the cartridge case is formed from a first case and a second case, and an ink pack and a press member are housed in the first case. Further, the edge of the opening of the case is sealed by a film member, thus realizing a sealed state. The second case prevents expansion of the film member, which would otherwise be caused when the film member receives pressurized air.
Preferably, a lug-shaped member is formed on the second case. A tapered surface and an engagement step section are formed on each lug-shaped member such that, when the second case is attached to the first case, the tapered surface goes beyond the flange section formed on the first case and such that the engagement step section engages the flange section.
In the ink cartridge according to the present invention, an ink pack which is formed from flexible material and is filled with ink is housed in a cartridge case along with an ink pack press member. In accordance with the volume of the press member, the volume of ink to be poured into the ink pack can be regulated.
In other words, a plurality of types of press members of different volumes are prepared. In accordance with the volume of ink filled in the ink pack, a press member is selected and housed in the cartridge case. The ink pack can be housed in the case without involvement of a large clearance and so as to substantially occupy the internal space of the case.
Without regard to whether the volume of ink filled in an ink pack is large or small, free movement of an ink pack within the cartridge case can be effectively prevented. As mentioned above, a problem of damage to an ink pack when the ink pack is subjected to physical shock during transport can be eliminated.
In this case, a window-shaped opening is formed in the center of the press member, whereby an ink-filled ink pack formed into a bag shape is retained by the press member such that the peripheral edge of the ink pack is pressed.
Consequently, the press member can be housed in the case to smoothly match the outer geometry of the ink pack. Therefore, holding of an ink pack when the ink pack is subjected to physical shock can be improved to a much greater extent.
When the foregoing configuration is applied to an ink cartridge in which pressurized air is introduced into a cartridge case, a press member whose volume is selected in accordance with the volume of ink filled in an ink pack is housed, and hence the volume of pressurized air to be introduced into the cartridge case can be caused to fall within a predetermined range.
Hence, there can be prevented a time lag that would arise from the time a recording apparatus is powered up to the time the recording apparatus enters a standby state, thereby improving throughput of the recording apparatus.
The present invention also provides an ink-jet recording apparatus into which an ink cartridge as defined in any one of claims 1 through 31 can removably mounted, comprising:
a recording head which is mounted on a carriage and reciprocatingly moved in a widthwise direction of recording paper; and
a sub-tank which is replenished with ink from an ink cartridge through an ink supply channel and supplies ink to the recording head, wherein
ink is supplied from the ink cartridge to the sub-tank by the action of air pressure applied to the ink cartridge.
In this case, the ink supply channel extending from the ink cartridge to the sub-tank is preferably formed from a flexible ink supply tube.
In a preferred embodiment, an ink supply valve is further provided in the ink supply channel extending from the ink cartridge to the sub-tank, and the ink supply valve is opened or closed in accordance with a control signal produced by ink level detection means for detecting the volume of ink remaining in the sub-tank.
In addition, an annular packing member is preferably provided in a cartridge holder to which the ink cartridge is removably mounted, and, while the ink cartridge is mounted the cartridge holder, the annular packing member comes into close contact with an outer peripheral surface of a cylindrical member which defines an air channel communicating with a pressure chamber of the ink cartridge.
In a preferred embodiment, a cartridge holder to which the ink cartridge is removably mounted is provided with an open/close valve unit which, when the ink cartridge is mounted to the cartridge holder, comes into contact with an ink outlet section of the ink cartridge and recedes axially, thus becoming open; and wherein, when no ink cartridge is mounted to the cartridge holder, the open/close valve unit advances axially, thus maintaining a closed state.
In this case, the open/close valve unit is preferably provided with a hollow needle having an ink inlet hole and a slide member; and wherein, when no ink cartridge is mounted to the cartridge holder, upon receipt of urging force of the spring member the slide member moves to a position where the slide member closes the ink inlet hole formed in the hollow needle.
In the ink-jet recording apparatus to which the ink cartridge according to the present invention is to be mounted, a required and sufficient amount of ink can be supplied to the sub-tanks provided on the carriage by the action of pressurized air.
Consequently, even in a recording apparatus in which ink is supplied to a sub-tank through a flexible ink supply tube from an ink cartridge, printing can be effected continuously without being affected by the dynamic pressure of the ink supply tube.
An open/close unit which advances in the axial direction when no ink cartridge is mounted to the cartridge holder, to thereby sustain a closed state is provided in a cartridge holder provided to the recording apparatus. As a result, when no ink cartridge is mounted to the cartridge holder, the open/close valve unit axially advances and is maintained closed, thereby preventing a problem of contamination, which would otherwise be caused by reverse flow of ink from the sub-tank.
The present disclosure relates to the subject matter contained in Japanese patent application Nos.
Hei. 11-288421 (filed on Oct. 8, 1999),
2000-21020 (filed on Jan. 31, 2000),
2000-24419 (filed on Feb. 1, 2000),
2000-186050 (filed on Jun. 21, 2000),
2000-201983 (filed on Jul. 4, 2000),
2000-12461 (filed on Jan. 21, 2000), and
2000-12462 (filed on Jan. 21, 2000),
which are expressly incorporated herein by reference in their entireties.